The 3 worst stocks in the stock market today all hail from the health care sector

Eight in 10 sectors and nearly two out of every three stocks finished as winners on Tuesday. Well-versed pessimists know the implications of that: two in 10 sectors were big, fat losers today, and more than one in three stocks ended more loathed than loved. An experienced pessimist might even notice that each of today's hardest-slumping laggards -- Gilead Sciences(NASDAQ:GILD), AbbVie(NYSE:ABBV), and Biogen Idec(NASDAQ:BIIB) -- all belong to the health care sector. "Healthcare stocks are going to hell in a handbasket!" they might warn, wishing they had handbasket-makers in their portfolios. Ignoring these imaginary pessimists and their irrational diversification desires, the S&P 500 Index(SNPINDEX:^GSPC) added 6 points, or 0.4%, to end at 1,851.

Gilead Sciences lost 3.1% today, as the chickens finally seem to be coming home to roost. A sharp sell-off in recent weeks among health care and biotech names was originally sparked by Congressional scrutiny upon Gilead itself. Three Democratic congressmen questioned the company's $84,000 annual pricetag for its hepatitis C drug Sovaldi, pointing out that the treatment is of little use to the afflicted if the price point can only be afforded by sultans and kings.

The imaginary pessimist mentioned in the first paragraph may actually be genetically wired to lose money in the stock market, but he or she was right about one thing: health care stocks were a mess on Tuesday. The sector lost 0.7%, the only area of the market to shed more than 0.1% of its value. AbbVie, which makes drugs treating autoimmune diseases, high cholesterol, and Parkinson's disease, among other maladies, tumbled 3% today. Last week AbbVie gave up on a legal dispute against the European Medicines Agency which sought to keep data from its clinical trials private. AbbVie's hasty attempts to keep its data guarded plant nothing but the idea of risk in the mind of investors. And pessimists and investors both despise unnecessary risk.

Lastly, shares of Biogen Idec shed 2.8% today, as Biogen continued to pay the price for merely being mentioned in the same breath as Gilead. Wall Street has a curious tendency to over-associate one stock with what it believes to be the most direct peers in that industry. The trouble is, sometimes a brief letter from three congressmen to a single company is just as trivial as it sounds; while I don't think Biogen itself is directly threatened by the "scrutiny" on Gilead, Biogen's recent slump shows just how delicately valued the stock was before the pessimists awoke from their slumber.